Improvement in screw-cutting machines



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Improvement in Screw Cutting Muachi'nes.

N0, 123,951, Patented Feb. 20, 1872.

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4Improveaflnenf in Screw Cutting Machines.

No. 123,951, Patented Feb.2o,1a72.

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UNITED STATES PATENT GEEIoE.

LEVI W. STOOKWELL, OF RAVENNA, OHIO.

IMPROVEMENT IN SCREW-CUTTING MACHINES.

Specification forming part of Letters Patent No. 123,951, dated February 20, 1872.

Specification describing certain Improvements in Bolt-Cutting Machines, invented by LEVI W. STocKWELL, of Ravenna, in the county of Portage and State of Ohio. Y

Figure l is a view of the top of the machine embodying my invention. Fig. 2 is a section of the front end of the cutter-head. Fig. 3 is a side view of a die and parts connected therewith. Fig. 4 is aright-hand-side view of parts shown in Fig. 3. Fig. 5 is a side elevation of a section of the machine.

A is the frame of the machine; B is the driving-pulley, which is hung on the shaft O; D is the face-plate, to which the cutter-head is bolted through holes in the flange on the back end ofthe cutter-head; E is the lever support, with aJ ring at one end, through which the cutter-head turns, and which is kept in its position by a shoulder on each side. The ringF is in a groove around the sliding collar H, which' turns in the ring. To the rings E and F is attached the jointed lever G. I is the part of the cutter-head which holds the dies J, and passes through the sliding collar H, which is moved back by the lever G to open the dies, and forward by the same lever to close the dies on the bolt. rIhe dies are connected with the sliding collar by the strut-levers K. The outer ends of the strut-levers are held and turn in the seats L, which are in the sliding collar and move with it, lhe other ends of the strut-levers are held and turned in the outer ends ofthe dies. M isa scroll, which may be turned on the sliding collarl one-third of the distance around it. The flanges on the seats L, shown at the upper right corner of Fig. 3, rest in the groove N which is in the scroll, and by means of which, when the scroll is turned on the sliding colla-r, the seats, strut-levers, and dies are moved in or out to adj ustthe dies for ditferent-sized bolts.Y There is a scale on the outside of the scroll at the ri ght-liand side, anda scale adjoining it on the outside ot' the sliding collar, one of them being a vernier. The vernier scale extends one-third of the circumference, and the other scale extends two-thirds ofthe circumference. 'lhe inside of the scroll has three cams, or as vmany as there are dies used, each extending one-third of the distance around the scroll. When the scroll is turned on the sliding collar, the dies are adjusted by these cams for difterent-sized bolts, and to compensate for wear of dies. rEhe vernier scale indicates what the adjustment is. One of the advantages ot' using the vernier scale is, that slight adjustments of the dies are indicated, while the division-lines on the scales are far enough apart to be easily seen and indexed by letters and figures.

When the lever G is moved back against the stop O, the dies are drawn out by the strutlevers, so that the bolt may be removed. To move the dies in to cut the bolt, the sliding collar is thrown forward by the lever G, so`that the strut-levers stand in line with the dies, and both the strut-levers and dies are at right angles with the bolt.l To remove and cha-nge the dies, the cap P, covering the face of the cutterhead, is slipped off, and the stop O is turned so that the lever G may be thrown far enough back to open the dies enough to bring the strutlevers at right angles with the dies, when the strut-levers may be taken out of the dies, and the dies drawn out and replaced by others.

The dies are cut by being placed in the grooves.

R R R, which are so made that the center line lengthwise of each die if extended would not pass through the axis of the cutter-head, but a little to one side ot' the axis. \Vhen in use, each die is placed (as shown in the drawing) in the groove opposite to the one in which it was cut, and where the center line of each die if extended would not pass through the axis of the cutter-head, but a little to the same side of the axis that it did when the die was in groove It. By rea-son of the center of these grooves not being cnt in the exact direction of the cutter-head, after the die is cut in the groove It, one side of the die projects beyond the opposite side, and when the die is in use in the opposite groove, where it appears in the drawing, the projecting side of the die-face cuts the thread ot' the bolt, and the opposite side of the die-face does not press against the bolt, and consequentlyY there is less friction than there would be if the whole face ot' the die was on a line with the circulnferei'lce of the bolt. The dies may also be used iu the grooves R R R, where they are out, and where each side of the die-face will be equally distant from the axis of the cutter-head. But when the cutting-side ofthe die-face is dull or worn, it will thread the bolt with much less friction by using it in the opposite groove, where it appears in the drawing.

S is the upper part of avessel which catches the oil and cuttings falling` from the machine, strains the oil through a sieve into the bottom of the vessel, from whence the oil is carried by the belt T passing; under the rollers U and over a rim or circular projection on the cap P, from the top of which the oil is scraped or led from the belt by the oil-leader V onto the bolt where the dies arel cutting. W is aringI forming1 part of the bolt-holder, with two horizontal pins projecting from opposide sides into the tubes, which are part ofthe sliding' collars that slide on the rods X fastened in the frame ofthe ma.- chine. The bolt is drawn between the dies and drawn out when cut by the sliding' ofthe boltholder on the rods X Inside ofthe ring` NV is the dog' Y, in which the bolt is held from turningby the screw Z,which passes looselyv throughy -the ring, and horizontally by means of the horizontal pins of the ring sliding;` freelyr in the tubes, and by these two motions combined it can move freely in any direction. By means of this movable bolt-holder, a bent or crooked bolt, which is not on a line where it is being,` cut with the part where it is held, may be so held that the part which is being' cut will be at right angles with the dies. The lever G is attached to the cutter-head only, and the cutter-head may be. attached to and operated by a lathe by simply bolting' it through the ange on the back end to the face-plate of the lathe.

l claim as my inventionl. The combination ofthe ring,` W, the sliding' collars on the rods X X, the dog Y, screw Z, and the spiral spring which forms the boltholder, substantially as and for the purpose herein set forth.

2. The belt for carrying the oil, in combination with the oil-vessel, the cutter-head, and oil-leader, substantially as and for the purpose hereinbefore set forth.

3. The combination ofthe reciprocating ring,` or scroll M, the seats or sockets L, the strutlevers K, and the dies J, substantially as and for the purpose herein set forth.

4. The combination of the dies, the strutlevers, the seats, the scroll, and sliding collar H, substantiallyr as and for the purpose here. inbefore set. forth.

5. The combination ofthe lever G, the leversupport and rin g E, the revolving' arbor ofthe cutter-head, the ring` F, the sliding,` collar H, and the two links which connect the lever-support E with the lever G, substantially as and for the purpose herein set forth.

LEVI NV. STOCKWELL.

Witnesses:

.BRADFORD HowLAND, ALEXANDER BJGRIFFIN. 

